INSPECTION PROCEDURE 2: When the Brake Pedal is Depressed, Auto-cruise Control is not Cancelled.: Diagnosis

Required Special Tool: 

• MB991223: Harness Set

1. STEP 1. Check if the stoplight illuminates. 

   Q: Is the stoplight illuminated? 

   YES  : Go to  Step 8.

   NO:  Go to Step 2.

2. STEP 2. Measure the 12-Volt supply circuit voltage at stoplight switch connector C-03. 
   1. Disconnect stoplight switch connector C-03.
      Fig 1: Disconnecting Stoplight Switch Connector C-03

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   2. Measure the voltage between stoplight switch connector C-03 terminal 2 and ground.
      • The voltage should measure battery positive voltage.

   Q: Is the measured voltage battery positive voltage? 

   YES  : Go to  Step 5.

   NO:  Go to Step 3.

   Fig 2: Measuring Voltage Between Stoplight Switch Connector C-03 Terminal 2 And Ground

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3. STEP 3. Check stoplight switch connector C-03 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Are the connector and terminals in good condition? 

   YES  : Go to Step 4.

   NO:  Repair or replace the faulty connector. (Refer to , HARNESS CONNECTOR INSPECTION ). Go to  Step 11.

   Fig 3: Checking Stoplight Switch Connector C-03

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4. STEP 4. Check the harness wire between relay box fuse number 11 and stoplight switch connector C-03 terminal 2 for damage. 

   Q: Is the harness wire in good condition? 

   YES  : It can be assumed that this malfunction is intermittent. (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS ). Go to  Step 11.

   NO:  Repair the damaged harness wire. Go to  Step 11.

   Fig 4: Checking Harness Wire Between Relay Box Fuse Number And Stoplight Switch Connector C-03

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5. STEP 5. Check the stoplight switch. 
   1. Disconnect harness connector C-03 at the stoplight switch.
      Fig 5: Disconnecting Harness Connector C-03 At Stoplight Switch

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   2. Connect an ohmmeter to the stoplight switch, and check continuity when the plunger of the stoplight switch is pushed in and when it is released.
   3. The stoplight switch is in good condition if the circuit is open when the plunger is pushed in to a depth of within 4 mm (0.2 inch) from the outer case edge surface, and if the resistance value is less than 2 ohms when it is released.
      Fig 6: Checking Stoplight Switch Continuity

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   4. The check for continuity should be made at terminals 1 and 2 of the stoplight switch.

   Q: Is the stoplight switch in good condition? 

   YES  : Go to Step 6.

   NO:  Replace the stoplight switch. (Refer to BRAKE PEDAL ). Go to  Step 11.

   Fig 7: Checking For Continuity Should Be Made At Terminals 1 And 2 Of Stoplight Switch

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6. STEP 6. Check stoplight switch connector C-03 and intermediate connector C-209 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Are the connectors and terminals in good condition? 

   YES  : Go to Step 7.

   NO:  Repair or replace the faulty connector. (Refer to , HARNESS CONNECTOR INSPECTION ). Go to  Step 11.

   Fig 8: Checking Stoplight Switch Connector C-03

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   Fig 9: Checking Intermediate Connector C-209

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7. STEP 7. Check the harness wire between stoplight switch connector C-03 terminal 1 and intermediate connector C-209 terminal 14 for damage. 

   Q: Is the harness wire in good condition? 

   YES  : It can be assumed that this malfunction is intermittent. (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS ). Go to  Step 11.

   NO:  Repair the damaged harness wire. Go to  Step 11.

   Fig 10: Checking Harness Wire Between Stoplight Switch Connector C-03

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   Fig 11: Checking Intermediate Connector C-209

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8. STEP 8. Measure the signal voltage at auto-cruise control-ECU connector C-21 by backprobing. 
   1. Do not disconnect auto-cruise control switch connector C-21.
   2. Turn the ignition switch to the "ON" position.
      Fig 12: Disconnecting Auto-Cruise Control Switch Connector C-21

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   3. Measure the voltage between auto-cruise control-ECU connector C-21 terminal 4 and ground by backprobing.
      • The voltage should measure battery positive voltage. (When brake pedal is depressed).
      • The voltage should measure 0.5 volts or less. (When brake pedal is not depressed).
   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Are all of the measured voltages satisfied? 

   YES  : Check that the malfunction is eliminated. If the malfunction is eliminated, it can be assumed that this malfunction is intermittent. (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS ). If the malfunction is not eliminated, replace the auto-cruise control-ECU (Refer to AUTO-CRUISE CONTROL  ), and then Go to  Step 11.

   NO:  Go to Step 9.

   Fig 13: Measuring Voltage Between Auto-Cruise Control-ECU Connector C-21 Terminal 4 And Ground

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9. STEP 9. Check auto-cruise control-ECU connector C-21 and intermediate connector C-209 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Are the connectors and terminals in good condition? 

   YES  : Go to Step 10.

   NO:  Repair or replace the faulty connector. (Refer to , HARNESS CONNECTOR INSPECTION ). Go to  Step 11.

   Fig 14: Checking Auto-Cruise Control-ECU Connector C-21

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   Fig 15: Checking Intermediate Connector C-209

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10. STEP 10. Check the harness wire between auto-cruise control-ECU connector C-21 terminal 4 and intermediate connector C-209 terminal 14 for damage. 

    Q: Is the harness wire in good condition? 

    YES  : Check that the malfunction is eliminated. If the malfunction is eliminated, it can be assumed that this malfunction is intermittent. (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS ). If the malfunction is not eliminated, replace the auto-cruise control-ECU (Refer to AUTO-CRUISE CONTROL  ), and then go to Step 11.

    NO:  Repair the damaged harness wire. Go to Step 11.

    Fig 16: Checking Harness Wire Between Auto-Cruise Control-ECU Connector C-21

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    Fig 17: Checking Intermediate Connector C-209

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11. STEP 11. Check that the malfunction is eliminated. 

    Q: Is the malfunction eliminated? 

    YES  : This procedure is complete.

    NO:  Go to  Step 1.